Four Israelis were shot dead in their car Tuesday near the West Bank settlement of Kiryat Arba less than a day before Israeli and Palestinian leaders meet in Washington for a summit to announce the resumption of direct peace talks. The attack, for which Hamas has claimed responsibility, shattered years of relative calm in the West Bank.

Rescue personnel examining the vehicle in which four residents of the Hebron area were killed, August 31, 2010.Tomer Appelbaum

The victims are a couple from the settlement of Beit Hagai and two residents of Kiryat Arba. One of the dead was a woman believed to have been pregnant.

The Beit Hagai couple has been identified as Yitzhak and Tali Ames, 45 and 47. They are survived by six children, the oldest 24 and the youngest 5. Just six months ago, the Ames couple celebrated the birth of their first granddaughter.

Tali worked as an account manager in various offices in the area and Yitzhak was a tour guide who accompanied groups to the Temple Mount area every Wednesday. Beit Hagai, a tiny settlement in the South Hebron Hills, is home to 100 families.

A spokesman for Hamas' military wing, the Iz al-Din al-Qassam Brigades, announced Tuesday that members of the organization carried out the shootings. A Hamas spokesman in Gaza, Sami Abu Zuhri, said the Islamist group praises the attack and considers it a natural response to "the crimes of occupation."

Another Hamas spokesman, Fawzi Barhoum, said the attack was meant to highlight the failure of the security cooperation between the Palestinian Authority and Israel.

A senior PA official who is in Washington for today's official launch of direct peace talks with Israel expressed outrage over the attack and accused Hamas of attempting to thwart the negotiations. The Fatah-dominated Palestinian security forces in the West Bank launched their own investigation into the incident in an effort to track down the gunmen.

The South Hebron Hills, where the attack took place, is considered an area in which Hamas cells have heightened their presence. The commander of the West Bank division, Brig. Gen. Nitzan Alon, said the authorities believe that Hamas is telling the truth in claiming the attack.

After the incident, Israeli troops and police were stationed at major checkpoints and junctions along West Bank roads in an effort to track down the gunmen. In addition, the police's operations branch has issued instructions to officers throughout the country to stay alert. The Israel Defense Forces said it had located the gunmen's car.

IDF sources said there had been no indications that an attack was imminent. Defense officials now believe that Palestinian terrorist organizations may seek to sabotage the peace negotiations. The authorities are also worried that far-right settlers may try to provoke unrest as well.

At around 7:30 P.M. on Tuesday, gunshots were heard near the Bnei Naim junction just south of Kiryat Arba. A preliminary investigation revealed that the gunmen drove alongside the car and opened fire. Authorities believe it is possible that after the driver was shot and the car was forced off the highway, the gunmen approached the vehicle to ensure that all the car's passengers had been killed.

Guy Gonen, a Magen David Adom paramedic who arrived at the scene, told Channel 2 that his crew saw "a car that was pierced with dozens of bullets and inside there were four bodies. There was absolutely no chance of helping."

Defense Minister Ehud Barak was briefed on the attack by IDF chief of staff Gabi Ashkenazi and Shin Bet chief Yuval Diskin. Barak conferred by telephone with Prime Minister Benjamin Netanyahu, who was on his way to Washington. He also spoke with Vice Prime Minister Silvan Shalom, who is serving as acting prime minister while Netanyahu is abroad.

"Unfortunately we are once again witness to the fact that while we are working to find ways to co-exist and create a reality of peace, there are those who continue to take the path of terror and are busy killing innocents," said Shalom.

"Today it is clearer more than ever that the real obstacle to peace is terrorism and the extremists who will do anything to send the entire region up in flames. It is incumbent on the Palestinian Authority to fulfill its obligations in the territories that are under its purview," Shalom said.

"We are giving full backing to the prime minister during the talks in the United States."

According to Barak, "This apparently is an attempt by depraved terrorists to harm efforts to move the diplomatic process forward and to try to harm the chances of peace talks that are beginning in Washington."

The attack prompted sharp reactions from West Bank settler leaders, who were quick to draw a link between the killings and the peace talks that are set to get underway. "It's about time that the leaders of Israel wake up from their delusions of an imaginary peace," said Zvi Bar Hai, the head of the South Hebron Hills regional council.

Lawmakers from right-wing parties called on Netanyahu to announce an immediate suspension of talks with the PA.

"Netanyahu must at once freeze the talks and concentrate on securing the peace for the citizens of Israel," said MK Uri Ariel (National Union ). "Now it is clear that the most violent period is when a diplomatic process is underway."

"Anyone who in recent months was complicit in building the myth of Abu Mazen [Palestinian President Mahmoud Abbas] as the one who is in control on the ground must sober up and immediately cease and desist from continued actions aimed at strengthening the Palestinian army, which is being gradually established under American sponsorship," said MK Aryeh Eldad (National Union ).

MK Tzipi Hotovely, a hawkish member of Netanyahu's ruling Likud faction, said: "The terrorist organizations are sending a clear message by resuming their attacks on innocent Israelis. This is a warning sign to anyone who believes that concessions over the Land of Israel will lead to a solution to the conflict. There needs to be a firm response to terrorism, not concessions."

Fellow Likud MK Ofir Akunis added: "Every time Israel extends its hand for peace, the Palestinians make every effort to cruelly cut it off. The entire world can see this evening that Israel seeks peace while the Palestinians seek terror and violence."

According to Science and Technology Minister Daniel Hershkowitz, "Unfortunately, this horrific attack once again proves that there is no partner on the Palestinian side and that we must now consider if there is any point in holding these discussions."

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